Modern antibot solutions and security guides on SpigotMC now specifically mention MCSpam.pw as a known threat to mitigate.
The .zip file is frequently found on "leaked" plugin repositories and underground forums like VeryLeaks and BlackSpigot , where users share tools for "griefing" or crashing servers. File Characteristics & Risks MCSpam.pw.zip
Files of this nature, especially when distributed as password-protected ZIPs or on unofficial forums, are frequently used to mask malware such as remote access trojans (RATs) or credential stealers. Modern antibot solutions and security guides on SpigotMC